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How to combine multiple conditions to subset a data-frame using “OR”?
... the following syntax before with lot of success when I wanted to use the "AND" condition.
3 Answers
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Do you (really) write exception safe code? [closed]
Exception handling (EH) seems to be the current standard, and by searching the web, I can not find any novel ideas or methods that try to improve or replace it (well, some variations exist, but nothing novel).
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What are the differences between Generics in C# and Java… and Templates in C++? [closed]
I mostly use Java and generics are relatively new. I keep reading that Java made the wrong decision or that .NET has better implementations etc. etc.
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How to combine two or more querysets in a Django view?
I am trying to build the search for a Django site I am building, and in that search, I am searching in 3 different models. And to get pagination on the search result list, I would like to use a generic object_list view to display the results. But to do that, I have to merge 3 querysets into one.
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How do I use a Boolean in Python?
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Actually Python didn't have a boolean type for a long time (as in old C), and some programmers still use integers instead of booleans.
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What is a stream?
...n a stream:
read one byte. Next time you read, you'll get the next byte, and so on.
read several bytes from the stream into an array
seek (move your current position in the stream, so that next time you read you get bytes from the new position)
write one byte
write several bytes from an array into...
List comprehension vs map
...re NOT making a lambda for the purpose, but using the same function in map and a listcomp). List comprehensions may be faster in other cases and most (not all) pythonistas consider them more direct and clearer.
An example of the tiny speed advantage of map when using exactly the same function:
$ p...
What is Serialization?
I am getting started with Object-Oriented Programming (OOP) and would like to know: what is the meaning of serialization in OOP parlance?
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SQL Server Text type vs. varchar data type [closed]
I have variable length character data and want to store in SQL Server (2005) database. I want to learn some best practices about how to choose TEXT SQL type or choose VARCHAR SQL type, pros and cons in performance/footprint/function.
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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
Ge...